Situational Awareness (Saturday, 2026-08-08)
Flows continue to hover around 2,000 cfs, the CO-OP threshold for daily drought monitoring. Over the past 24 hours, most portions of the basin have received trace amounts to 0.5 inches of rain. According to the Middle Atlantic River Forecast Center predictions, little rain is expected over the next 3 days. The 10-day outlook expects a total of about one inch of rain in the basin.
Special Conditions
The National Park Service has informed us that the annual off-water inspection at Potomac Dam No. 4 in Washington County, MD, will take next week (Tuesday, August 11, 2026). During this time, the hydroelectric operator – Eagle Creek Renewables will be diverting water off of the run-of-river dam crest through their powerhouse turbines. This will cause intra-daily flow fluctuations at the Point of Rocks gage.
Daily flows:
Little Falls gage flow 2026-08-07: 1571 MGD (2430 cfs)
Little Falls gage flow 2026-08-08: 1713 MGD (est., based on recently available real-time data) (2650 cfs)
Note: Gage flow at Little Falls is measured after water supply withdrawals.
Point of Rocks flow 2026-08-07: 1318 MGD (2040 cfs)
Point of Rocks flow 2026-08-08: 1306 MGD (est., based on recently available real-time data) (2020 cfs)
Yesterday's estimated daily flows:
Great Falls estimated flow 2026-08-07: 1571 MGD (2431 cfs)
Note: Estimated flow below Great Falls intake is flow at Little Falls plus Little Falls water supply withdrawal.
Yesterday's Washington metropolitan area Potomac River withdrawals and discharges (2026-08-07):
Fairfax Water Corbalis withdrawal - Potomac: 98 MGD
WSSC Water Potomac withdrawal: 151 MGD
Washington Aqueduct withdrawal - Great Falls: 136 MGD
Washington Aqueduct withdrawal - Little Falls: 0 MGD
Loudoun Water withdrawal: 12 MGD
Loudoun Water Broad Run discharge: 6 MGD
Total Potomac withdrawal: 397 MGD
Total net Potomac withdrawal: 391 MGD
Loudoun Water Potomac River (PR) flow values for drought operations protocol (based on yesterday's flows):
QPR: 2040 cfs
QPR, obs: 2040 cfs
QPR, WS: 0 cfs